This research mainly focuses on the divergences and controversies over defining terrorism and how to define, understand and deal with terrorism. Based on the systematic survey and study of previous definitions about terrorism and fully referring to other relevant information and data, this article is devoted to exploring the main characteristics and nature of terrorism, then putting forward a clear, pragmatic and widely accepted definition of terrorism from a relatively unique perspective, and then not only tries to use it as a tool to explain, clarify and solve the problems relating to terrorism in reality, but also deepen the battle against the intangible conception of terrorism by proposing some suggestions to strike at the tangible entity of terrorist organizations and terrorists.